.a American patent above shows a application for a design, applied for in 1912.

Catalogues I have here, show this model/design available in Europe1911....makes sense to me being the home of the fan . Stands to reason the application date for the patent in Italy would be a lot earlier ...too

Fan shown in above patent is what I refer to as a flat faced 8 vent hole motor. .

Marellis first 12" ac motor was a 12 vent pancake , pictured on the left. .on right is the 16" version Pampero

Charles Eck introduced his Eck Hurricane in 1903 in the U.S. To my knowledge, Eck's design is the first direct drive oscillator unless somebody knows anything else. If you're interested in a starting point, perhaps Ercole Marelli saw this design and found inspiration.
My 1907 Marelli catalog (in french) has no mention of oscillating fans. We know there is a 1912 patent filed in the U.S. So a Nordico with 12 vent holes logically could not be sold any earlier than 1908.

However, from a business perspective, I can't understand why Marelli, with such a great fan as the Nordico is, would wait from 1908 to 1911 to use advertising material to tell customers about the new oscillators. That just doesn't make sense to me.
It could be that Marelli concurrently offered the 12-vent oscillator and the 8-vent oscillator?

But these are just my observations. Now, as to why not many of the 12-vent fans might not be around ...

Those Marelli pancake motors suffer from worn bearings because of heavy rotors -- like their counterparts, the pancakes in the U.S. The 8-vent hole motors are not light, but these as well as the later Marellis with the easily removable brass sleeve bearings -- usually wear less.

In a nutshell, the 12-vent pancake motor is heavier and is more prone to wear. But ... I digress.

When you have a worn bearing, that creates vertical play in the shaft. When you have a shaft with a worm pressed onto it, you have a shaft with a worm pressed on it with vertical play in a worn bearing. The worm wheel ... bull gear ... whatever it is called ... is then spinning adjacent to a shaft that is moving up and down against the gear's threads. What happens? You get a worn out gear that won't work and a fan that won't oscillate.

I assume worn out fans leading up to both World Wars sometimes would've been scrapped for munitions.

The worn bearing/oscillator assembly is one piece on the early Marelli oscillators. If you were take the bearing/oscillator assembly out of the fan and examine it in your hand, what you would find would be the bearing is actually pressed/soldered in a very exact fit into the u-shaped bracket that is the oscillator assembly that holds the gear. So while it physically appears to be one piece ... it is actually constructed from two pieces.